<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        #div0{
            display: flex;
            width: 400px;
            height: 500px;
            background-color: violet;
        }
        #div0 div{
            width: 100px;
            height: 200px;
            background-color: yellow;
            /*第三个属性设置为auto时 width生效*/
            /*flex: 0 0 auto;*/
            /* 1 1 auto*/
            flex: auto;
        }

    </style>
</head>
<body>
    <div id="div0">
        <div></div>
        <div></div>

    </div>
</body>
</html>
